Has any world class runner had 5 years+ away and come back to run at the same world-class level?

NO!

John Campbell might qualify.

http://sportsillustrated.cnn.com/vault/article/magazine/MAG1139859/index.htm

Ben Johnson.

How about Derartu Tulu? She won an OG medal in 2004, then to my knowledge did not do much until 2009, when she won the NYC Marathon (at age 37)

Derartu Tulu, possibly. Not sure how long she was out before the 2009 NYC Marathon, but it seemed like a lot when she won that year.

Ruth Wysocki had about a 4 year break. '88 to 92

Major Meets:

1973 7)USA 800

1973 7)USA Junior 800

1976 4)USA 1500

1976 8)Olympic Trials 800

1976 4h)Olympic Trials 1500

1977 9)USA 800

1978 1)USA 800

1984 2)USA 800

1984 2)Olympic Trials 800

1984 1)Olympic Trials 1500

1984 6)Olympic Games 800

1984 8)Olympic Games 1500

1985 3)USA 1500

1986 7)USA 1500

1987 12)USA 1500

1987 8)GP Final 3000

1988 4)Olympic Trials 1500

1988 6)Olympic Trials 3000

1988 4)GP Final 1500

1992 11)Olympic Trials 1500

1995 4)USA 1500

1995 7)World Championships 1500

1996 14)Olympic Trials 1500

Ron Clarke had at least three years off before returning to competition.

Sydney Wooderson was out for most of WW2 but came back to run well between 1946 and 1948. From Wiki:

He was the natural choice to carry the Olympic torch into Wembley stadium for the 1948 Summer Olympics. However he was turned away at the last minute because members of the organising committee wanted a more handsome final runner.

???

Daniel Komen

Mr. Obvious wrote:

Daniel Komen

Haha

Wallace Speamon ran faster than ever after being off almost two decades.

Same with Calvin Smith but with his 9.93 speed now gone, he had to move up to the 400m.

Moe's Tavern wrote:

Same with Calvin Smith but with his 9.93 speed now gone, he had to move up to the 400m.

you're kidding, right? Please?

agip wrote:

Moe's Tavern wrote: Same with Calvin Smith but with his 9.93 speed now gone, he had to move up to the 400m.

you're kidding, right? Please?

He never went away but, Ken Griffey's name has stretched across the major leagues for 37 years and still going strong. Thirty-one year spread as an All-Star.

Apples and oranges though.

worknesh kidane took 4 years off to have 2 kids, did not train at all during those 4 years, she is not all the way back to her best yet, but she is getting there.